My Inquiry
My Account
Texas Instruments SN74LS245DWG4
- Part No.:
- SN74LS245DWG4
- Manufacturer:
- Texas Instruments
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
SN74LS245DWG4.pdf
- Description:
- IC TXRX NON-INVERT 5.25V 20SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,646
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74LS245DWG4 from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between A and B buses in TTL-level systems. It features direction control (DIR), active-low output enable (OE), 8 ns typical propagation delay, ±15 mA high-level/24 mA low-level output drive, and hysteresis-enhanced noise immunity on bus inputs - used in industrial backplane interfaces and legacy embedded bus isolation.
For engineers reviewing the SN74LS245DWG4 datasheet, SN74LS245DWG4 pinout, SN74LS245DWG4 application, or SN74LS245DWG4 equivalent, key selection criteria include 5 V operation, SOIC-20 package compatibility, 3-state bus isolation capability, and LS-family logic level interoperability with legacy microcontrollers and peripheral interfaces.
Technical Context
The SN74LS245DWG4 implements Schottky transistor–transistor logic (TTL) with PNP input structures to reduce DC loading on shared bus lines. Its DIR pin selects data flow direction (A→B or B→A), while OE enables or disables all eight channels simultaneously into high-impedance state.
It operates within 4.75 V to 5.25 V supply range at 0 °C to 70 °C ambient, delivering VOH ≥ 2.4 V at –15 mA and VOL ≤ 0.5 V at 24 mA sink current. Input hysteresis (0.2–0.4 V) improves noise margins on both A and B bus terminals.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | LS-TTL - compatible with standard 5 V TTL systems and legacy controllers |
| Supply Voltage | 4.75 V to 5.25 V - requires stable 5 V rail; bypass capacitor mandatory per TI layout guidance |
| Propagation Delay | 8 ns typical (tPLH/tPHL) - supports up to ~100 MHz bus toggle rates under light load |
| Output Drive | –15 mA source / +24 mA sink - sufficient to drive ribbon cables and unterminated backplanes |
| Input Hysteresis | 0.2–0.4 V - increases noise immunity on shared bus lines in electrically noisy environments |
| ESD Rating | ±2500 V HBM - meets JEDEC JS-001; handling requires ESD-safe practices |
| Operating Temperature | 0 °C to 70 °C - commercial-grade rating suitable for non-military embedded applications |
Pinout & Package
SN74LS245DWG4 is housed in a 20-pin SOIC (DW) package measuring 12.80 mm × 7.50 mm, with gull-wing leads and RoHS-compliant NiPdAu plating. The package supports surface-mount reflow per Level-1-260°C MSL rating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | DIR | Direction control input: LOW = B→A, HIGH = A→B - determines real-time data path polarity |
| 2–9 | A1–A8 | A-side bidirectional I/O - connect to master-side bus; function as input or output based on DIR state |
| 10 | GND | Ground reference - must be low-impedance connection to minimize switching noise |
| 11–18 | B8–B1 | B-side bidirectional I/O - connect to slave/backplane bus; role mirrors A-side per DIR setting |
| 19 | OE | Active-low output enable - HIGH disables all outputs to high-Z, isolating A and B buses |
| 20 | VCC | +5 V power supply - requires local 0.1 µF ceramic bypass capacitor per TI recommendation |
Key Features
| Feature | Design Value |
|---|---|
| 3-State Output Control | Single OE pin disables all eight channels simultaneously, enabling clean bus arbitration and hot-swap isolation |
| PNP Input Structure | Reduces DC loading on driven bus lines - critical for maintaining signal integrity across long ribbon cables |
| Hysteresis on All Bus Inputs | 0.2–0.4 V threshold window improves noise rejection in factory automation and test equipment environments |
| Standard '245 Pinout | Pin-compatible with industry-standard octal transceivers - simplifies drop-in replacement in legacy designs |
| TTL-Level Compatibility | Direct interface with 5 V MCUs, FPGAs, and peripheral ICs without level-shifting circuitry |
Applications
| Industrial Backplane Interface | Legacy MCU Bus Extension |
|---|---|
Use Scenario: Connecting a microcontroller unit to a multi-slot industrial backplane carrying sensor and actuator signals. IC Role / Device Role / Timing Role: Bidirectional bus driver and isolator - buffers weak MCU outputs and prevents bus contention during hot-plug events. Use Value: Enables reliable 5 V TTL communication over 30+ cm ribbon cables by boosting drive strength and suppressing noise-induced glitches. |
Use Scenario: Extending address/data bus of an 8051 or Z80-based embedded controller to off-board memory or peripherals. IC Role / Device Role / Timing Role: Synchronous bus transceiver - provides direction-controlled data routing with sub-12 ns timing margin. Use Value: Maintains setup/hold timing integrity across PCB splits while allowing software-controlled bus direction reversal. |
| Test Equipment Signal Routing | Factory Automation I/O Hub |
Use Scenario: Reconfigurable signal path in automated test equipment where DUT interfaces must be dynamically isolated or connected. IC Role / Device Role / Timing Role: Programmable bus gate - OE and DIR pins controlled by FPGA to route stimuli/responses between instrument modules. Use Value: Eliminates need for mechanical relays; supports >10⁶ switching cycles with deterministic 25–40 ns enable/disable latency. |
Use Scenario: Centralized I/O aggregation node in PLC rack systems interfacing discrete sensors and actuators via parallel bus. IC Role / Device Role / Timing Role: Robust bus repeater - drives multiple downstream loads while rejecting EMI from motor drives and solenoids. Use Value: Hysteresis and 24 mA sink capability prevent false triggering in electrically harsh factory environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal bus transceiver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LS245N | PDIP-20 package; same electrical specs but through-hole mounting; higher RθJA (46.1 °C/W vs 79.0 °C/W) | Suitable for prototyping or legacy through-hole PCBs; not for space-constrained SMT layouts | Select when manual assembly, breadboarding, or socket-based field repair is required |
| SN74LS245DBR | SSOP-20 package; identical logic and timing; smaller footprint (7.20 mm × 5.30 mm); same RoHS/NiPdAu finish | Better suited for high-density boards; requires finer-pitch reflow profile than SOIC | Choose for compact industrial controllers where board area is constrained but SOIC rework is impractical |
Compared with SN74LS245N and SN74LS245DBR, the SN74LS245DWG4 offers the broadest manufacturing support among SOIC variants, balances thermal performance (79.0 °C/W RθJA) with ease of hand-soldering, and remains actively stocked for legacy system maintenance.
Availability
SN74LS245DWG4 is available at Aetrix Electronics and suitable for industrial backplane interfaces, legacy MCU bus extensions, and test equipment signal routing requiring stable component supply across extended product lifecycles.
Supply support for SN74LS245DWG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with over five decades of innovation in industrial and automotive electronics.
The SN74LS245DWG4 belongs to TI's legacy LS-TTL logic family, engineered for robust 5 V bus interfacing in industrial control, instrumentation, and retro-computing applications where reliability and long-term availability are critical.
FAQ
What is the operating voltage range for SN74LS245DWG4?
The SN74LS245DWG4 operates from 4.75 V to 5.25 V. Operation outside this range may cause unreliable logic states or damage. TI specifies that supply decoupling with a 0.1 µF ceramic capacitor placed near the VCC pin is mandatory to suppress switching noise and ensure stable performance across temperature.
How does the DIR pin control data flow in SN74LS245DWG4?
In SN74LS245DWG4, the DIR pin determines direction: when DIR is HIGH, data flows from A-side inputs (pins 2–9) to B-side outputs (pins 11–18); when DIR is LOW, data flows from B-side to A-side. This bidirectional control enables flexible bus architecture without external multiplexers or additional logic.
Can SN74LS245DWG4 replace SN74LS245N in an existing design?
Yes, SN74LS245DWG4 is functionally identical to SN74LS245N and shares the same pinout, timing, and electrical specifications. However, the DWG4 uses SOIC packaging versus PDIP, so PCB layout and soldering process must be updated - no changes to logic design or firmware are needed.
What is the maximum output current capability of SN74LS245DWG4?
The SN74LS245DWG4 delivers –15 mA source current (IOH) and +24 mA sink current (IOL) per channel under recommended conditions. Exceeding these values risks exceeding absolute maximum ratings and may degrade long-term reliability or cause thermal shutdown in sustained high-load scenarios.
Does SN74LS245DWG4 include built-in ESD protection?
Yes, SN74LS245DWG4 features ±2500 V human-body model (HBM) ESD protection per JEDEC JS-001. While this exceeds standard requirements, TI recommends grounding leads during handling and using conductive foam storage to prevent latent damage - especially during manual assembly or rework.
SN74LS245DWG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74LS
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Logic Type:
- Transceiver, Non-Inverting
- Number of Elements:
- 1
- Number of Bits per Element:
- 8
- Input Type:
- -
- Output Type:
- 3-State
- Current - Output High, Low:
- 15mA, 24mA
- Voltage - Supply:
- 4.75V ~ 5.25V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOIC
SN74LS245DWG4 FAQ
1.How can I place an order for SN74LS245DWG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74LS245DWG4 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SN74LS245DWG4 reliable?
The price and inventory of SN74LS245DWG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74LS245DWG4 is usually 5 days.
3.What payment methods are accepted for SN74LS245DWG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74LS245DWG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74LS245DWG4?
SN74LS245DWG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74LS245DWG4 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SN74LS245DWG4?
For technical support, including SN74LS245DWG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74LS245DWG4 requirements.
6.How does Aetrix verify that SN74LS245DWG4 is sourced from the original manufacturer or authorized distributors?
All SN74LS245DWG4 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SN74LS245DWG4 meets industry standards.
7.What is the process for return or replacement of SN74LS245DWG4?
All SN74LS245DWG4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74LS245DWG4, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SN74LS245DWG4 part is unused and in its original packaging.
Return procedure for SN74LS245DWG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74LS245DWG4 Tags
-
SN74LVC1G17DBVR
Texas Instruments
-
SN74LVC1G07DCKR
Texas Instruments
-
SN74LVC1G17DCKR
Texas Instruments
-
SN74LVC1G07DBVR
Texas Instruments
-
SN74LVC1G125DCKR
Texas Instruments
-
SN74AHCT1G126DBVR
Texas Instruments
-
SN74LVC1G125DBVR
Texas Instruments
-
SN74AHCT1G125DBVR
Texas Instruments
-
SN74LVC2G17DBVR
Texas Instruments
-
SN74LVC2G07DCKR
Texas Instruments
-
SN74LVC1G34DCKR
Texas Instruments
-
SN74LVC2G17DCKR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
